Easy open container with pressure release and safety feature

ABSTRACT

Surging of the granular contents of a container at a pressure greater than ambient and having an end closure provided with a weakened score line and an opening device cooperating with the closure is prevented by a diaphragm disposed below the closure and above the container contents. The container closure is of the type that when a closure area defined by a weakened score line is removed, a sharp edge remains adjacent the container flange. The diaphragm has a removable central portion defined by a weakened line having openings therethrough to equalize the pressure on both sides of the diaphragm. When the closure area is removed, the openings in the diaphragm gently release the pressure in the container to prevent surging of the granular contents. The diaphragm has a removable center section defined by the weakened line and said openings for removal of the contents. The locus of the weakened line is inboard of the sharp edge, and upon removal of the center section, the remanent portions of the diaphragm serve as a shield for the sharp edge.

United States Patent Kennedy et al.

[54] EASY OPEN CONTAINER WITH PRESSURE RELEASE AND SAFETY FEATURE [72] Inventors: James E. Kennedy, Spanish Fort, Ala.; Melvin A. Koboldt, St. Louis,

[73] Assignee: Container Corporation of America,

Chicago, Ill. [22] Filed: April 26, 1971 [2]] Appl. No.: 137,453

[151 3,690,506 51 Sept. 12, 1972 Primary ExaminerGeorge T. Hall Attorney-Carpenter, Ostis & Lindberg [57] ABSTRACT Surging of the granular contents of a container at a pressure greater than ambient and having an end closure provided with a weakened score line and an opening device cooperating with the closure is prevented by a diaphragm disposed below the closure and above the container contents. The container clo sure is of the type that when a closure area defined by a weakened score line is removed, a sharp edge remains adjacent the container flange. The diaphragm has a removable central portion defined by a weakened line having openings therethrough to equalize the pressure on both sides of the diaphragm. When the closure area is removed, the openings in the diaphragm gently release the pressure in the container to prevent surging of the granular contents. The diaphragm has a removable center section defined by the weakened .line and said openings for removal of the contents. The locus of the weakened line is inboard of the sharp edge, and upon removal of the center section, the remanent portions of the diaphragm serve as a shield for the sharp edge.

4 Claims, 4 Drawing Figures mzminsmzwn 3.690.506

F|G.4 INVENTORS JAMES E. KENNEDY MELVIN A. KOBOLDT ATTORNEYS EASY OPEN CONTAINER WITH PRESSURE RELEASE AND SAFETY FEATURE BACKGROUND OF THE INVENTION The invention herein relates to containers of the type having end closures including a line of weakness whereby the closure is able to be opened by the operation of a pull tab. When such containers are packed with granular material having the property of emitting gases such as ground coffee, the opening thereof gives rise to suring of the contents. Oftentimes the surging is of such a degree that a considerable amount of the product may be ejected from the container.

The operation of the pull tab and the rupturing of the top closure along a line of weakness leaves a cut edge dangerous to the user of the product in the container.

The structure of the prior invention is directed to the prevention of surging of the contents of the container upon the rupturing of the closure thereof, and for protecting the hands of the userfrom the sharp edge of the closure afterthe center panel has been removed.

The Prior Art The prior art is best exemplified in the following patents:

SUMMARY OF THE INVENTION The structure according to the present invention makes it possible to open a container under a pressure greater than the ambient without surging of the contents, where the container is of the type having a closure with a line of weakness capable of being ruptured by the operation of a pull tab. Such initial operation of the tab, but for the structure of the present invention, gives rise to surging of the contents within the container. The surging is prevented by a diaphragm disposed below the closure and spaced a small distance therefrom. It has a line of weakness therein with openings therethrough enabling the pressure on both sides thereof to be equal.

When the top closure is ruptured, the tiny openings in the diaphragm permit venting of the container, and the slow release of the gases therein to prevent surging of the contents. The diaphragm has a center removable panel defined by a line of weakness, therein for removal of the same, and the locus of the line of weakness and the openings are inboard of the cut edge so as to protect the hands of th user.

THE DRAWING FIG. 1 is a perspective view of the closure and of a cylindrical container having the improvements according to the present invention therein;

FIG. 2 is a vertical sectional view through the container of FIG. 1 showing details of the top closure thereof, structure for rupturing the top closure and structure for preventing the surging of the contents of the container when the top closure is ruptured;

FIG. 3 is a perspective view of a diaphragm adapted to be used with the structure seen in FIG. 2; and

FIG. 4 is a partial vertical sectional view showing a alternate form of holding the diaphragm in position.

The improved container-according to the present invention is referred to generally by the reference numeral 10, and includes a cylindrical body 11 which may have its lower end closed by a conventional closure, not shown, since such forms no part of the present invention. The upper end of the body 11 is closed by a rupturable closure 12 having an inner portion 13 and an outer portion 14, the two portions being joined along a circular line of weakness 15. The closure 12 and the body 11 are secured in sealed relationship, such as by a conventional double seam 17, which includes an inner annular countersink wall 18 and an outer doubled upon itself seam 19. The upper end of the can body 11 is also doubled upon itself as seen at 21 to form double seam 17.

Structure is provided for separating from the inner portion 13 from outer portion 14 along line of weakness l5, and comprises a conventional lift tab 22 with a pull ring 23, lift tab 22 being pivoted at a riveted member 24 formed in the portion 13. Tab 22 has a force supplying edge 26 spaced from the rivet 24 and adapted to rupture the top closure 12 along the line of weakness 15 in a manner well known in the art.

Such rupturing of the top closure 12 causes a rapid ejection of gas from the container carrying in the stream thereof a granular product stored within the container under a pressure greater than the ambient. After such initial rupturing of the top closure 12, center panel 13 may be removed in a manner well known in the art, and such operation results in a raw edge 27 being formed at the edge of the outer portion 14, see FIG. 4.

Structure is provided for preventing the surging of the granular material upon rupturing of the closure 12 and for venting the gases within the container 10 at a rate preventing such surging. Such structure is also provided for the purpose of shielding the raw edge 27, so that the user of the contents in the container may do so safely.

.To this end there is provided a diaphragm 30 disposed below the closure 12 in close proximity thereto and having a line of weakness 31 defined in part by a plurality of closely spaced, transversely spaced aperture 32 of very small extent and arranged to equalize the pressure on both sides of diaphragm 30.

As seen in FIG. 2 the diaphragm is of a'thickness of the order of a 0.010 inch and is enabled to be held in position by a body head 33 formed in the wall of the container body 11. The diaphragm 30 in such case is made of a fiberboard or the like, and has sufficient rigidity to be held in position between the inturned body head 33.

After the conclusion of the rupturing of the top closure 12, and after the pressure beneath the diaphragm 30 has been released through the apertures 32 a central panel 34 thereof may be removed by means of a lift tab 36 as seen in FIG. 3. When center panel 34 is removed, there remains in position an annular ring 37 underlying the outer portion 14 of the upper closure 12, the inner edge of the annular ring 37 beinginboard of the raw edge 26 of the outer portion 14.

Alternately and as seen in FIG. 4 a metallic diaphragm 40 may be retained at its edges in the double seam 17 between portion 21 of can body 11 and closure 12. Diaphragm 40 may be constructed of a foil of a suitable type, such as aluminum, having a thickness of 0.001 inch and to 0.00015 inch, and the same may be provided with a center panel like panel 34 of FIG. 3. Said panel is capable of removal as with the embodiment seen in said FIG. 3. After the removal thereof, the annular rim 41 of the diaphragm remains in position to protect the raw edge 27. Pull tab 36 is provided for removal of the center panel therefrom.

Alternately there may be provided a laminar film of 0.0035 inch in thickness and held in position as seen in FIG. 4 between closure 12 and body 11, or placed into position into the body 11 beneath the closure 11 beneath the closure 12, such film may be press fitted into container body 11 beneath closure 12, and would be provided with a removable center panel causing an annular portion to remain protecting the cut edge 27.

It will be seen at several structures according to the present invention serve a two-fold function in that they can relieve excessive pressure within the container upon rupturing of the closure thereof without surging of the contents. Moreover, the structures according to the present invention makes it possible to protect the 'raw edge remaining from the removal of the center portion of the closure for protection of the consumer.

We claim:

1. A container for granular or pulverulent products under pressure greater than that of the ambient comprising:

a. a container body;

b. a rupturable closure secured to said body including inner and outer portions defined by a line of ii. said inner portion being detachably connected to said outer portion at said line of weakness;

iii. the removal of said inner portion resulting in a raw edge in said outer portion;

c. means for preventing surging of said granular material upon rupturing of said closure and for providing a protective shield for said raw edge when said inner portion is removed, said means comprising a diaphragm disposed below said closure in close proximity thereto and having a weakened line therein,

i. said line of weakness including openings through said diaphragm to equalize the pressure on opposite sides thereof;

ii. said openings and said line defining a removable center panel therein;

iii. said openings and said line being on a locus inboard of said raw edge whereby upon removal of said inner portion and said removable center panel said raw edge is protected by remanent portions of said diaphragm.

2. A container according to claim 1 wherein said diaphragm is retained in position at the edge thereof by a bead formed in the wall of said container.

3. A container according to claim 1 wherein said diaphragm is press fitted into said container body below said closure.

4. A container according to claim 1 wherein said diaphragm is in the form of a metal foil retained between said can body and said clo sure. 

1. A container for granular or pulverulent products under pressure greater than that of the ambient comprising: a. a container body; b. a rupturable closure secured to said body including inner and outer portions defined by a line of weakness; i. said outer portion being secured to said container; ii. said inner portion being detachably connected to said outer portion at said line of weakness; iii. the removal of said inner portion resulting in a raw edge in said outer portion; c. means for preventing surging of said granular material upon rupturing of said closure and for providing a protective shield for said raw edge when said inner portion is removed, said means comprising a diaphragm disposed below said closure in close proximity thereto and having a weakened line therein, i. said line of weakness including openings through said diaphragm to equalize the pressure on opposite sides thereof; ii. said openings and said line defining a removable center panel therein; iii. said openings and said line being on a locus inboard of said raw edge whereby upon removal of said inner portion and said removable center panel said raw edge is protected by remanent portions of said diaphragm.
 2. A container according to claim 1 wherein said diaphragm is retained in position at the edge thereof by a bead formed in the wall of said container.
 3. A container according to claim 1 wherein said diaphragm is press fitted into said container body below said closure.
 4. A container according to claim 1 wherein said diaphragm is in the form of a metal foil retained between said can body and said closure. 